U.S. patent number 5,701,251 [Application Number 08/564,283] was granted by the patent office on 1997-12-23 for method and system for constructing the figures of blanks in sheet metal work.
This patent grant is currently assigned to Kabushiki Kaisha Komatsu Seisakusho. Invention is credited to Yukio Yoshimura.
United States Patent |
5,701,251 |
Yoshimura |
December 23, 1997 |
Method and system for constructing the figures of blanks in sheet
metal work
Abstract
A blank-figure constructing method for sheet metal work, wherein
a cutting passage planned to sequentially cut a plurality of
desired blanks from a sheet material is determined, utilizing a
multiple figure composed of the figures of the plurality of blanks
to be obtained, in the multiple figure of which the adjacent line
segments of the single blank figures are combined. This method is
that if the multiple figure has an even number of, four or more odd
vertices at each of which an odd number of internal and external
line segments of the multiple figure meet, an auxiliary line is
drawn outside the multiple figure, connecting any two of the odd
vertices on the outline of the multiple figure to make the total
number of odd vertices be two or zero so that the cutting passage,
which passes through all the internal, external line segments and
auxiliary line of the multiple figure, can be determined.
Inventors: |
Yoshimura; Yukio (Ishikawa,
JP) |
Assignee: |
Kabushiki Kaisha Komatsu
Seisakusho (Tokyo, JP)
|
Family
ID: |
16259262 |
Appl.
No.: |
08/564,283 |
Filed: |
December 29, 1995 |
PCT
Filed: |
June 24, 1994 |
PCT No.: |
PCT/JP94/01026 |
371
Date: |
December 29, 1995 |
102(e)
Date: |
December 29, 1995 |
PCT
Pub. No.: |
WO95/04315 |
PCT
Pub. Date: |
February 09, 1995 |
Foreign Application Priority Data
|
|
|
|
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Jul 30, 1993 [JP] |
|
|
5-190508 |
|
Current U.S.
Class: |
700/182; 83/49;
83/75.5; 83/55; 83/40; 83/39; 83/13; 700/117; 700/122; 700/187;
700/167; 700/171; 345/418; 345/443; 345/441; 345/442 |
Current CPC
Class: |
G06Q
10/043 (20130101); Y10T 83/0529 (20150401); Y10T
83/155 (20150401); Y10T 83/0572 (20150401); Y10T
83/04 (20150401); Y10T 83/0524 (20150401); Y10T
83/06 (20150401) |
Current International
Class: |
G06Q
10/00 (20060101); G06F 017/50 (); G06F
019/00 () |
Field of
Search: |
;364/474.24,474.25-474.26,468.01,468.24,469.01,474.01,474.08,474.13,474.16
;83/13,34-35,39-40,49,52,55-56,75.5,797,798
;395/118,133-135,141-143 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
62-69301 |
|
Mar 1987 |
|
JP |
|
5-19831 |
|
Jan 1993 |
|
JP |
|
5-61999 |
|
Mar 1993 |
|
JP |
|
Primary Examiner: Voeltz; Emanual T.
Assistant Examiner: Dam; Tuan Q.
Attorney, Agent or Firm: Nikaido, Marmelstein, Murray &
Oram LLP
Claims
I claim:
1. A blank-figure constructing method for sheet metal work wherein
a cutting passage planned to sequentially cut a plurality of
desired blanks from a sheet material is determined, utilizing a
multiple figure composed of the figures of the plurality of blanks
to be obtained, in the multiple figure of which the adjacent line
segments of the single blank figures are combined, if the multiple
figure has an even number of, four or more odd vertices at each of
which an odd number of internal and external line segments of the
multiple figure meet, an auxiliary line is drawn outside the
multiple figure, connecting any two of the odd vertices on the
outline of the multiple figure to make the total number of odd
vertices be two or zero so that the cutting passage, which passes
through all the internal, external line segments and auxiliary line
of the multiple figure, can be determined.
2. The blank-figure constructing method for sheet metal work as
claimed in claim 1, wherein said auxiliary line is angled and/or
curved.
3. The blank-figure constructing method for sheet metal work as
claimed in claim 1 or 2, which is applied to a computer-aided
design system and/or a computer-aided manufacturing system.
4. The blank-figure constructing method for sheet metal work as
claimed in claim 1 or 2, wherein said sheet material is a steel
plate, non-ferrous sheet material or non-metal sheet material.
5. The blank-figure constructing method for sheet metal work as
claimed in claim 1 or 2, wherein gas cutting, arc cutting, electron
beam cutting, laser cutting or water jet cutting is performed to
form the blanks.
6. A blank-figure constructing system for sheet metal work wherein
a cutting passage planned to sequentially cut a plurality of
desired blanks from a sheet material is determined, utilizing a
multiple figure composed of the figures of the plurality of blanks
to be obtained, in the multiple figure of which the adjacent line
segments of the single blank figures are combined, comprising
auxiliary line drawing means for drawing an auxiliary line outside
the multiple figure, if the multiple figure has an even number of,
four or more odd vertices at each of which an odd number of
internal and external line segments of the multiple figure meet, to
connect any two of the odd vertices on the outline of the multiple
figure so that the total number of odd vertices becomes two or
zero,
wherein the cutting passage, which passes through all the internal,
external line segments and auxiliary line of the multiple figure,
is determined.
7. The blank-figure constructing system for sheet metal work as
claimed in claim 6, wherein said auxiliary line is angled and/or
curved.
8. The blank-figure constructing system for sheet metal work as
claimed in claim 6 or 7, which is applied to a computer-aided
design system and/or a computer-aided manufacturing system.
9. The blank-figure constructing system for sheet metal work as
claimed in claim 6 or 7, wherein said sheet material is a steel
plate, non-ferrous sheet material or non-metal sheet material.
10. The blank-figure constructing system for sheet metal work as
claimed in claim 6 or 7, wherein gas cutting, arc cutting, electron
beam cutting, laser cutting or water jet cutting is performed to
form the blanks.
Description
1. Technical Field
The present invention relates to a blank-figure constructing method
and system for sheet metal work and, more particularly, to a
blank-figure constructing method and system which are adapted in
use for sheet metal work to determine the positions of blanks on a
sheet material to cut therefrom and to determine a passage for
cutting the blanks.
2. Background Art
Japanese Patent Publication Laid-Open No. 5-19831 (1993) discloses
a prior art blank-figure constructing method and system for use in
sheet metal work. According to this publication, a multiple figure,
which is composed of a plurality of figures corresponding to a
plurality of desired metal blanks to be cut from a sheet material,
is constructed on the sheet material such that the adjacent line
segments of the figures corresponding to the blanks are combined as
shown, for instance, in FIG. 3. When sequentially cutting the
plurality of blanks from the sheet material, the cutting passage is
determined such that priority is given to the longer line segment
and further to a line segment closer to the presently cutting
position.
In the above method and system, since a cutting passage is
determined by simply giving precedence to a longer or nearer line
segment, it is impossible to find a cutting passage which passes
through all the internal and external line segments of the multiple
figure in cases where the multiple figure has four vertices at each
of which an odd number of internal and external line segments meet
as shown, for instance, in FIG. 3 (this vertex is hereinafter
referred to as "odd vertex"). In such cases, cutting cannot be
continuously performed and therefore the initial operation of
cutting (i.e., piercing etc.) has to be performed more than once,
which limits the speed of the cutting operation.
The invention has been made in consideration of the foregoing
problem and one of the objects of the invention is therefore to
provide a blank-figure constructing method and system for sheet
metal work, which enables continuous, high-speed cutting.
DISCLOSURE OF THE INVENTION
The above object can be achieved by a blank-figure constructing
method for sheet metal work according to the invention, wherein a
cutting passage planned to sequentially cut a plurality of desired
blanks from a sheet material is determined, utilizing a multiple
figure composed of the figures of the plurality of blanks to be
obtained, in the multiple figure of which the adjacent line
segments of the single blank figures are combined, if the multiple
figure has an even number of, four or more odd vertices at each of
which an odd number of internal and external line segments of the
multiple figure meet, an auxiliary line is drawn outside the
multiple figure, connecting any two of the odd vertices on the
outline of the multiple figure to make the total number of odd
vertices be two or zero so that the cutting passage, which passes
through all the internal, external line segments and auxiliary line
of the multiple figure, can be determined.
The above object can be also achieved by a blank-figure
constructing system for sheet metal work according to the
invention, wherein a cutting passage planned to sequentially cut a
plurality of desired blanks from a sheet material is determined,
utilizing a multiple figure composed of the figures of the
plurality of blanks to be obtained, in the multiple figure of which
the adjacent line segments of the single blank figures are
combined, comprising auxiliary line drawing means for drawing an
auxiliary line outside the multiple figure, if the multiple figure
has an even number of, four or more odd vertices at each of which
an odd number of internal and external line segments of the
multiple figure meet, to connect any two of the odd vertices on the
outline of the multiple figure so that the total number of odd
vertices becomes two or zero,
wherein the cutting passage, which passes through all the internal,
external line segments and auxiliary line of the multiple figure,
is determined.
First of all, it should be noted that the cutting passage that
passes through all the internal and external line segments of the
multiple figure can be obtained only when one of the following
conditions are met.
1. Where the cutting start point and the cutting end point differ
from each other, each point is an odd vertex at which an odd number
of line segments meet.
2. Where the cutting start point and the cutting end point are the
same, this point is a vertex at which an even number of line
segments meet (this vertex is hereinafter referred to as "even
vertex").
3. Each of vertices other than the cutting start point and the
cutting end point is an even vertex at which an even number of line
segments meet.
Since the cutting passage that passes through all the line segments
can be obtained under the above conditions, when the multiple
figure has four odd vertices as in the example mentioned before,
such a passage cannot be obtained and therefore continuous cutting
is impossible. However, continuous cutting can be performed by the
following arrangement. Taking FIG. 4 for example, of the four odd
vertices (i.e., vertices a, b, c, f), two odd vertices (i.e.,
vertices b and c) on the outline of the multiple figure are linked
by an auxiliary line t, whereby these odd vertices b and c
respectively become an even vertex and, as a result, the total
number of odd vertices in the multiple figure becomes two.
Accordingly, in cases where the multiple figure has an even number
of, four or more odd vertices, an auxiliary line is drawn outside
the multiple figure so as to connect the vertices on the outline of
the multiple figure among these odd vertices, whereby a cutting
passage that passes through all the internal, external line
segments and auxiliary line can be determined to perform continuous
cutting in the order indicated by arrows in FIG. 4.
The above-described construction of blank figures for sheet metal
work is preferably performed with a computer-aided design system
(CAD) or computer-aided manufacturing system (CAM) and the
auxiliary line may be angled and/or curved.
The sheet material may be a steel plate, non-ferrous sheet material
such as Al and Ti, or non-metal sheet material such as ceramics and
plastics. Cutting performed in the invention is preferably gas
cutting, arc cutting, electron beam cutting, laser cutting or water
jet cutting. The internal and external line segments may be
straight or curved.
Other objects of the present invention will become apparent from
the detailed description given hereinafter. However, it should be
understood that the detailed description and specific example,
while indicating preferred embodiment of the invention, are given
by way of illustration only, since various changes and
modifications within the spirit and scope of the invention will
become apparent to those skilled in the art from this detailed
description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 to 5 are associated with a preferred embodiment of a
blank-figure constructing method and system for sheet metal work
according to the invention.
FIG. 1 is a schematic diagram of a metal sheet cutting system
including a console-type computer.
FIGS. 2/1 and 2/2 are flow charts of the fundamental process of a
CAD/CAM program.
FIG. 3 is a diagrammatic view of a multiple figure.
FIG. 4 is an explanatory diagram showing a cutting passage in the
multiple figure.
FIG. 5 is a schematic diagram showing a cutting passage in another
multiple figure corresponding to FIG. 4.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring now to the drawings, a blank-figure constructing method
and system for sheet metal work will be described according to an
embodiment of the invention.
FIG. 1 schematically illustrates a metal sheet cutting system S
that comprises (i) a console-type computer 10 incorporating a
computer-aided design system (CAD) and computer-aided manufacturing
system (CAM) to which a blank-figure constructing system according
to the invention is applied; (ii) a laser cutter 20 for cutting a
sheet material with laser beams; and (iii) a numerical control unit
30 for automatically controlling the operation of the laser cutter
20. The console-type computer 10 comprises (i) a central processing
unit (CPU) 10A for executing the program for the CAD/CAM; (ii) a
read only memory (ROM) 10B for storing this program; and (iii) a
random access memory (RAM) 10C that serves as a working memory
including various registers used in the arithmetic operations
necessary for executing the program. Connected to the computer 10
are a key board 11 and a mouse 12 which serve as input devices.
Also, a display unit 13 and a floppy disk drive 14 are connected to
the computer 10 as output devices. According to the data input
through the key board 11 and mouse 12, arithmetic operations based
on the aforesaid program are performed. While results yielded by
the arithmetic operations are displayed on the display unit 13,
they are finally written, as NC data for cutting, in a floppy disc
inserted in the floppy disc drive 14. The laser cutter 20
comprises. (i) a work table 21 having a clamper (not shown) that
holds down a sheet material along the direction of the X-axis (see
FIG. 1) at the base end (i.e., the end of the laser cutter 20 when
viewing the cutter 20 in the direction of the Y-axis in FIG. 1);
(ii) a carriage 22 that is moved back and forth on the work table
21 in the direction of the Y-axis by means of a Y-axis driving
motor (not shown); (iii) a laser head 23 that is moved back and
forth along the carriage 22 in the direction of the X-axis by means
of an X-axis driving motor (not shown). The numerical control unit
30 comprises (i) a central processing unit (CPU) 30A for executing
an NC control program; (ii) a read only memory (ROM) 30B for
storing this program; and (iii) a random access memory (RAM) 30C
that serves as a working memory including various registers used in
the arithmetic operations necessary for executing the program. The
processing unit and memories used in the numerical control unit 30
are similar to those of the console-type computer 10 described
earlier. Also, the numerical control unit 30 is provided with an
operation panel 31 serving as an input device and connected to a
floppy disc drive 32. In the system comprised of the
above-described members, according to data input by the operation
panel 31, the NC data is read from the floppy disc written in the
console-type computer 10, inserted in the floppy disk drive 32.
Based on the aforesaid program, various arithmetic operations are
executed to drive the Y-axis and X-axis driving motors, so that the
carriage 22 and the laser head 23 are driven and the sheet material
placed on the work table 21 is cut into a desired shape. Note that
the process for the execution of the NC control program is known
and therefore will not be described herein.
Now, reference will be made to the flow chart of FIG. 2 to describe
the fundamental process of the program for the computer-aided
design system CAD and computer-aided manufacturing system CAM. In
this description, the figures of a plurality of blanks to be cut
from a sheet material are input by the key board 11 and/or mouse 12
and combined into a multiple figure as shown in FIG. 3. For
combining single blank figures, translation operation such as
parallel operation or rotational operation is performed according
to the operation of the key board 11 and/or mouse 12 with the
method disclosed in Japanese Patent Publication Laid-Open No.
5-19831 (1993). In the multiple figure thus obtained, the adjacent
line segments of the single figures are overlapped with each
other.
S-1: The number of odd vertices, at each of which an odd number of
internal and external line segments of the multiple figure meet, is
calculated. The multiple figure shown in FIG. 3 has four odd
vertices which are vertices a, b, c and f.
S-2, S-3: A check is made to judge whether the number of odd
vertices in the multiple figure is 1. If so, it is then determined
that not all of the external line segments in the multiple figure
are linked to one another so that the figure is not entirely closed
by lines. This does not satisfy the precondition of the multiple
figure necessary for continuous cutting and therefore the display
unit 13 indicates "the figure is not closed (unclosed figure)".
S-4, S-5: If it is determined in Step S-2 that the number of odd
vertices in the multiple figure is not 1, then a check is made to
judge whether the number of odd vertices is two. If the number is
two, the program proceeds to Step S-12. If the number is not two, a
check is then made to judge whether the number of odd vertices is
three or more. If the number is not three or more, the program
proceeds to Step S-18.
S-6, S-7: If it is determined in Step S-5 that the number of odd
vertices is three or more, a check is then made to judge the number
of odd vertices is an even number. If not, continuous cutting
cannot be performed and therefore the display unit 13 indicates
"continuous cutting is impossible".
S-8, S-9: If it is determined in Step S-6 that the multiple figure
has an even number of odd vertices, a check is further made to
judge whether three or more of the odd vertices exist inside the
outline of the multiple figure. If so, continuous cutting cannot be
performed, because an auxiliary line (described later) must not be
drawn inside the outline of the multiple figure. Therefore, the
display unit 13 indicates "continuous cutting is impossible".
S-10: If it is determined in Step S-8 that three or more of the odd
vertices do not exist inside the outline of the multiple figure,
and more precisely, if the multiple figure has an even number of, 4
or more odd vertices and 3 or more of them do not exist inside the
outline of the multiple figure, two external odd vertices will be
selected under the following conditions in order to connect them.
The multiple figure shown in FIG. 3 is categorized into this case,
as it has four odd vertices a, b, c and f and the vertex f is
positioned inside the outline of the multiple figure. Therefore, in
the case of the multiple figure shown in FIG. 3, two odd vertices
are selected from the odd vertices a, b and c positioned on the
outline of the multiple figure under the following conditions and
connected by an auxiliary line.
(1) First, the vertex, which is most unlikely to be the cutting
start point, is selected. In this embodiment, the vertex most
likely to be the cutting start point (this vertex is initially set)
is the nearest to zero in the X-coordinate and the furthest from
zero in the Y-coordinate, so that the odd vertex to be firstly
selected is the furthest from zero in the Y-coordinate and the
nearest to zero in the X-coordinate.
(2) Second, the vertices, between which the shortest auxiliary line
can be drawn are selected.
(3) The vertices to be selected should be such that the absolute
value of the angle between the auxiliary line to be drawn and the
X-axis or Y-axis is small. In other words, the auxiliary line
should be as parallel to the X-axis or Y-axis as possible.
In this way, the odd vertices b and c in the multiple figure shown
in FIG. 3 are selected.
The two odd vertices thus selected are linked by an auxiliary line
such that a preliminarily set distance is kept between the two odd
vertices and the two turning points on the auxiliary line in the
direction of the X-axis or Y-axis. This auxiliary line is
positioned outside the outline of the multiple figure, running at
the shortest distance between the two odd vertices. In the case of
the multiple figure shown in FIG. 3, points g, h are so determined
that distance is kept between these points g, h and the odd
vertices b, c in the direction of the Y-axis, and the points g, h
are linked by a straight line as shown in FIG. 4 so that an
auxiliary line in the form of ! is formed outside the outline of
the multiple figure.
S-11: A check is made to judge whether the number of odd vertices
becomes two due to the provision of the auxiliary line. If not, the
program returns to Step S-10 to draw another auxiliary line outside
the outline of the multiple figure. This process is repeated until
the number of odd vertices becomes two. In the case of the multiple
figure shown in FIG. 3, the addition of the auxiliary line t allows
the multiple figure to have two odd vertices a and f, as shown in
FIG. 4.
S-12: If it is determined in Step S-4 that the multiple figure has
two odd vertices, or if it is determined in Step S-11 that the
number of odd vertices in the multiple figure having the auxiliary
line is two, a cutting start point is determined so as to meet the
following conditions.
(1) Odd vertices on the outline of the multiple figure including
the auxiliary line have priority over odd vertices (i.e., inner odd
vertices) positioned inside the outline of the multiple figure
including the auxiliary line. The reason for this is that if an
inner odd vertex is selected as the cutting start point, piercing
cannot be performed at a point distant from the cutting start point
so that piercing has to be undesirably carried out on the inner odd
vertex.
(2) In cases where the multiple figure including the auxiliary line
has two odd vertices on its outline or two odd vertices inside the
outline, the odd vertex which is more likely to be the cutting
start point (this vertex is initially set) is selected. In this
embodiment, the odd vertex to be selected as the cutting point is
nearer to zero in the X-coordinate and further from zero in the
Y-coordinate.
In the multiple figure including the auxiliary line t and shown in
FIG. 4, the odd vertex a is thus selected as the cutting start
point, with the point P determined as the piercing point.
S-13: For start cutting, one line segment is selected from an odd
number of line segments which meet at the odd vertex selected as
the cutting start point. This selection is done according to the
following order of priority (this order is initially set).
(1) Priority is given to line segments having a lead end which does
not constitute an odd vertex of the multiple figure including the
auxiliary line. These line segments should not be selected as a
"cutting line segment" in previous selection.
(2) Priority is given to internal line segments, namely, line
segments which do not constitute the outline of the multiple figure
including the auxiliary line. This is because if all external line
segments (i.e., line segments which constitute the outline of the
multiple figure including the auxiliary line) are cut, the blank
portion still having internal line segments therein will be
separated from the sheet material, so that the internal line
segments cannot be cut after the separation.
(3) Where the odd vertex has two or more internal line segments,
the internal line segment whose angle to the X-axis has a smaller
absolute value is selected.
In compliance with the above order, the line segment a-d is
selected in the case of the multiple figure that includes the
auxiliary line t as shown in FIG. 4.
S-14 to S-16: A check is made to judge whether the lead end of the
selected line segment is the cutting end point. If so, a check is
then made to judge whether there still exist line segments which
have not been selected as a cutting line segment but meet at the
cutting end point. If there are no such line segments, the display
unit 13 indicates "the end of the program (END)".
S-17: It is determined in Step S-14 that the lead end of the
selected line segment is not the cutting end point, or if it is
determined in Step S-15 that there still exist unselected line
segments, one line segment is selected as a cutting line segment
according to the order of priority explained in Step S-13 from the
remaining unselected line segments that meet at the vertex where
the lead end of the selected line segment is positioned. Then, the
program returns to Step S-14.
The cutting passage is thus determined. In the case of the multiple
figure including the auxiliary line t and shown in FIG. 4, the
cutting passage starts from the odd vertex a (i.e., cutting start
point) and proceeds in the direction of arrows shown in FIG. 4,
sequentially passing through the internal, external line segments
and auxiliary line a-d, d-c, c-b, b-a, a-e, e-d, d-f, f-b, b-g,
g-h, h-c and c-f.
S-18: If it is determined in Step S-5 that the multiple figure has
not 3 or more odd vertices, and if no odd vertices exist in the
multiple figure, one of the even vertices at each of which an even
number of internal and external line segments meet will be selected
as a cutting start point according to the following order of
priority.
(1) Even vertices that constitute the outline of the multiple
figure have priority over even vertices (inner even vertices) that
are positioned inside the outline of the multiple figure for the
same reason as noted earlier in the case of odd vertices.
Specifically, if an inner even vertex is selected as the cutting
start point, piercing cannot be performed at a point distant from
the cutting start point so that the inner even vertex is
undesirably set as the piercing point.
(2) In cases where the multiple figure has even vertices only on
the outline or where it has even vertices only inside the outline,
the even vertex which is more likely to be the cutting start point
(this vertex is initially set) is selected, similarly to the case
of odd vertices. In this embodiment, the even vertex more likely to
be the cutting start point is nearer to zero in the X-coordinate
and further from zero in the Y-coordinate.
In the multiple figure shown in FIG. 5, the even vertex a' is
accordingly selected as the cutting start point, with the point P'
determined as the piercing point.
S-19: A cutting line segment is selected from the even number of
line segments which meet at the selected even vertex, according to
the same order of priority as described in Step S-13.
In this way, the line segment a'-d' is selected in the case of the
multiple figure shown in FIG. 5.
S-20 to S-22: A check is made to judge whether the lead end of the
selected line segment is the cutting start point. If so, a check is
then made to judge whether there still exist line segments which
have not been selected as a cutting line segment and which
constitute the cutting start point. If there are no such line
segments, the display unit 13 indicates "the end of the program
(END)".
S-23: It is determined in Step S-20 that the lead end of the
selected line segment is not the cutting start point, or if it is
determined in Step S-21 that there still exist unselected line
segments, one line segment is selected as a cutting line segment
from the unselected line segments which meet at the even vertex
that join the lead end of the selected line segment, according to
the order of priority described in Step 19. Then, the program
returns to Step S20.
In this way, the cutting passage is determined. In the case of the
multiple figure shown in FIG. 5, the cutting passage starts from
the even vertex a' (i.e., cutting start point) and proceeds in the
direction of arrows shown in FIG. 5, sequentially passing through
the internal and external line segments a'-d', d'-b', b'-a', a'-e',
e'-d', d'-c', c'-b', b'-f' and f'-a'.
In the invention, not only steel plates but also non-ferrous sheet
material such as Al and Ti and non-metal sheet material such as
ceramics and plastics can be used as the sheet material.
While a laser cutter is used in the embodiment, a gas cutter, arc
cutter, electron beam cutter, water jet cutter or the like may be
used.
In the foregoing embodiment, the blank-figure constructing system
of the invention is applied to a console-type computer in which
both computer-aided design system and computer-aided manufacturing
system are installed. However, it is also applicable to a
console-type computer in which either computer-aided design system
or computer-aided manufacturing system is installed. In addition,
the computer is not limited to the console-type but other types may
be employed.
Although the auxiliary line is drawn in the form of ! in the
embodiment, it may alternatively assume the form of <. In other
words, the auxiliary line may be angled and/or curved as far as it
connects two selected odd vertices. The internal and external line
segments constituting the multiple figure may be straight or
curved.
In the embodiment, NC data is transferred from the console-type
computer 10 to the numerical control unit 30, using a floppy disc
as a medium. It is also possible to employ a communication line to
transform it from the console computer 10 to the numerical control
unit 30.
The invention being thus described, it will be obvious that the
same may be varied in many ways. Such variations are not to be
regarded as a departure from the spirit and scope of the invention,
and all such modifications as would be obvious to one skilled in
the art are intended to be included within the scope of the
following claims.
Industrial Applicability
It is understood from the foregoing description that, according to
the invention, if the multiple figure has an even number of, four
or more odd vertices, an auxiliary line is so drawn as to connect
two odd vertices on the outline of the multiple figure, whereby a
cutting passage that passes through all the internal and external
line segments and auxiliary line of the multiple figure can be
determined. This arrangement enables continuous cutting which leads
to an increase in the speed of cutting operation. The method and
system of the invention find a useful application particularly in
the computer-aided design system and/or computer-aided
manufacturing system.
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